The present invention relates to a control apparatus for a fuel metering system of an internal combustion engine, and in particular for controlling the position of a fuel quantity-determining member of a diesel engine fuel pump. The apparatus includes a drive pedal transducer, a subsequent signal processing unit and a starting signal transducer.
In connection with a diesel engine, a control apparatus for the position of a member of a fuel pump determining the fuel injection quantity is known. This control apparatus includes, as noted above, a drive pedal sensor, a signal processing unit, and a starting signal transducer. During the engine starting procedure, a predetermined temperature-dependent starting fuel quantity is pre-specified in the case of the known control apparatus, this fuel quantity being brought about by a corresponding triggering of a final control element for the fuel quantity-determining member. The important feature is that the position of the fuel quantity-determining member of the fuel pump is defined during starting solely by the output signal of the control unit. While in theoretical terms the known system functions in a satisfactory manner, problems have arisen in practical operation. This is because of the fact that during the starting process, particuarly with a battery which is already weak, the supply voltage for the control unit can drop to such an extent that the control unit no longer emits precisely defined output signals. In this case, then, it is a necessary consequence that the required starting fuel quantity is not attained either.